Malicious PDF — malware analysis report

Static analysis result for SHA-256 fb9817c81154d96a…

MALICIOUS

PDF

78.3 KB Created: 2021-05-02 15:31:38 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-05-23
MD5: c1a5f2587b1632a8b2c0f770804fd6fe SHA-1: f54e3913f841cef38c667881140d70c6c6f353a5 SHA-256: fb9817c81154d96a321209f34d1b03329a229554b38e94105384b41ee7c086fc
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. Heuristics identified it as a link farm pointing to compromised CMS upload storage and disposable hosting, suggesting a phishing or malware distribution scheme. The embedded URLs, such as http://az4group.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1606f0a34daa3b---kajifoto.pdf, are likely used to redirect users to malicious sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9997

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • PDF link farm points to compromised-WordPress upload storage medium PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM
    PDF contains multiple clickable links, across many distinct hosts, whose targets are random-slug files parked in the upload directories of vulnerable WordPress form plugins (FormCraft, Super Forms). This is the hallmark of the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains hosted on compromised sites. The PDF itself carries no exploit — the risk is the linked destinations.
  • Small PDF is a non-clustered link farm on disposable hosting medium PDF_SEO_DISPOSABLE_LINK_FARM
    Small PDF contains many clickable external PDF links spread thin across many distinct hosts (no single dominant host), corroborated by a utm_term SEO-redirector link and/or links parked on free/disposable content hosts. This is the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains, rather than a normal document citation pattern. The PDF itself carries no exploit — the risk is the linked destinations.
  • External URI info PDF_URI
    PDF contains an external URL action
  • Object number defined twice with different bodies info PDF_DUPLICATE_OBJ_BODY_INCREMENTAL
    The same indirect object (N G) is defined more than once with different body bytes. First-wins and last-wins readers will resolve different content, which is a parser-confusion shape used by targeted PDFs. Body-only differences are common in benign incremental updates, so severity is raised only when the duplicate carries active content.
  • Embedded URL info EMBEDDED_URL
    One or more URLs were extracted from the document. The URL itself is not a detection — see the per-URL labels for which channel (macro, JS, link annotation, document body, ...) reached each URL.
    URL https://givemeit.ru/wp-content/plugins/super-forms/uploads/php/files/cb10c91d4c4599a9112937527436adbe/10783956993.pdf In PDF document text
    • http://az4group.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1606f0a34daa3b---kajifoto.pdfIn PDF document text
    • https://glasschneider.koeln/wp-content/plugins/super-forms/uploads/php/files/9b22434ppd1cppo5m4rf27rr93/zituwatorizok.pdfIn PDF document text
    • http://slowjamsundays.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606d95787afad---12169474334.pdfIn PDF document text
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607f1bb4af368---dabilegajabubinunabox.pdfIn PDF document text
    • http://lalitas-thaimassage-spa.de/wp-content/plugins/formcraft/file-upload/server/content/files/1608332becb98b---56697710546.pdfIn PDF document text
    • https://www.picmephotoboothhire.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/1607d4b46835a6---gofufovumomi.pdfIn PDF document text
    • https://aawyx.com/sites/default/imageuser/file/lazok.pdfIn PDF document text
    • https://lakecountyoralsurgery.com/wp-content/plugins/formcraft/file-upload/server/content/files/16088f0260d5d8---42556259640.pdfIn PDF document text
    • https://www.themeshcowork.com/wp-content/plugins/super-forms/uploads/php/files/664b9eb6888b8660fc1646051213042b/58634263044.pdfIn PDF document text
    • http://xn--e1aazeoc7d.xn--p1ai/images/shared/file/66841776304.pdfIn PDF document text
    • https://movesforfree.com/wp-content/plugins/super-forms/uploads/php/files/9sh9svm51kq4nqe7daahu3k7h7/35068902660.pdfIn PDF document text
    • https://tucsonhomewindowtint.com/wp-content/plugins/super-forms/uploads/php/files/42b080b62bdd0e4226c8bd2696a1dc7e/mezuvudotufika.pdfIn PDF document text
    • http://krindustria.com.br/site/wp-content/plugins/formcraft/file-upload/server/content/files/16089d275f2cbd---zalapemewasewa.pdfIn PDF document text
    • https://kamber.dk/wp-content/plugins/super-forms/uploads/php/files/03c287ce85e37e95cb779473c7bca9d3/83905134941.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/A3Ryygt5BCM/uplcv?utm_term=android+sdk+versions+and+namesPDF link annotation
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#In PDF document text
    • http://purl.org/dc/elements/1.1/In PDF document text
    • http://ns.adobe.com/pdf/1.3/In PDF document text
    • http://ns.adobe.com/xap/1.0/In PDF document text
    • http://ns.adobe.com/xap/1.0/mm/In PDF document text
    • http://ns.adobe.com/xap/1.0/rights/In PDF document text
    • http://scripts.sil.org/OFLIn PDF document text

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000f49e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF49E 5052 bytes
SHA-256: e2af792bc03a6041c671d384bc02c3bd9a8c273ff39a373e65a110b34e6cf54e
font_01_sfnt_off000105c0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x105C0 11212 bytes
SHA-256: 5f3105ef76265cea92ef7e23eb01325d48a97874b199c42c5c3aca1d3036e28a